Organic Light Emitting Devices (referred herein as “OLED” or “OLEDs”) represent a promising technology for display applications. For full color display applications, red-emitting, green-emitting and blue-emitting OLEDs with satisfactory performance are desired. Although in terms of efficiency and brightness, OLEDs can be utilized in the majority of display applications, their luminance stability continues to be a limiting factor, especially for blue-emitting OLEDs. Although recent advances have led to the realization of red-emitting and green-emitting OLEDs with a half-life exceeding 10,000 hours, thus making them suitable for a number of commercial applications (e.g., avionic and automotive displays, and personal and hand held electronics), luminance stability of blue-emitting OLEDs is still limited in many instances to about 1,000 hours, rendering them unsuitable for many of these applications. Therefore, there is still a need, addressed by embodiments of the present invention, to increase the luminance stability of OLEDs emitting in various colors in general, and in blue in particular, to make them suitable for utilization in a wide variety of commercial applications.
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